http://www.pcgamer.com/the-warmonger-tribe-joins-middle-earth-shadow-of-wars-orcish-menagerie/

You might reasonably think that the orcs of Middle-earth are, in general, warmongers. They quite clearly like to dive headlong into battle and kill people and burn and pillage and partake in all the parts of war that typically constitute mongering. But it turns out that there is a particular tribe of Orcs in the upcoming Middle-earth: Shadow of War that really enjoys the rough stuff. They are—you guessed it—the Warmonger Tribe.  

The Warmongers bring fury, so the trailer says. They also bring doom. Additionally, they bring "a storm of terror, misery, and slaughter." And of course, they bring war. The upside is that they appear to bring war to their orcish cousins as much as anyone else, which by rights should enable the good guys to adopt a policy of containment and monitoring: Establish a defensive buffer, keep a tactical force prepped to plug the holes, and let the whole thing burn itself out.